The publications U.S. Pat. No. 7,008,226, WO 2009/109057 and WO 2009/055952 (all to Woodwelding) disclose devices and methods for attaching a suture to hard tissue with the aid of a suture anchor, wherein the suture anchor comprises a material having thermoplastic properties and is anchored in a hard tissue opening with the aid of preferably vibratory energy used for in situ liquefaction of the material having thermoplastic properties. The liquefied material penetrates into pores or other suitable structures of the hard tissue of the wall of the hard tissue opening, where on re-solidification it constitutes a positive fit connection between the hard tissue and the suture anchor. The anchor comprises the material having thermoplastic properties on a circumferential surface or in the form of a thermoplastic sleeve and it is liquefied when the anchor is forced into the hard tissue opening and simultaneously vibrated or when the anchor or part thereof is positioned in the hard tissue opening and the thermoplastic sleeve is held between a vibrating tool and a counter element. The suture is threaded through the proximal or distal end of the suture anchor.
Further suture anchors and methods for fixating sutures to hard tissue are disclosed in the publications U.S. Pat. No. 7,678,134, U.S. Pat. No. 7,695,495, US-2006/161159, 2009/192546, US-2009/187216 (all to Arthrex), U.S. Pat. No. 5,733,307 (Dinsdale), or U.S. Pat. No. 6,508,830 (Steiner), wherein the disclosed anchors comprise an interference screw to be screwed into a bone opening provided for the purpose, or a plug preferably made of bone material to be press-fitted into a bone opening provided for the purpose, wherein the suture is either held by the screw or plug or by an additional element being retained in the opening with the aid of the screw or plug.
Methods of anchoring an item in an opening provided in hard tissue, e.g. in bone tissue of a human or animal patient with the aid of a material having thermoplastic properties which is liquefied in situ and made to penetrate the hard tissue of the wall of the opening are furthermore disclosed in the publications U.S. Pat. No. 7,335,205, US-2006/0105295, US-2008/109080, US-2009/131947, WO-2009/109057, and WO-2009/132472. Therein preferred energy used for the liquefaction is mechanical vibration energy. The disclosure of all the named publications and applications is enclosed herein by reference.